Two-fold combo-cooler

ABSTRACT

A two-fold combo cooler comprising non gas cooler and gas cooler portions, is provided, particularly for use in an assembly. An assembly having a gas combo-cooler has been found especially useful in automotive applications.

This patent application claims priority of Provisional Application No.60/777,598 filed on Feb. 28, 2006

FIELD OF THE INVENTION

Heat exchangers, having tubes, manifolds, and fins, and particularlyuseful in automotive applications, are described.

BACKGROUND OF THE INVENTION

A combo-cooler is a cooler with one or more heat exchangers(multi-exchangers) sharing the same frontal area. For example, acombo-cooler can comprise a condenser and an oil-cooler portion, the oilcooler and condenser portion connected with a common pair of manifolds,and tubes connected with fins. The combo-cooler can be considered as anentire module or assembly, the main portions of the module, includingtubes, fins and manifolds, can be assemble at the same time, providingsaving in assembling cost (for example, heater core assembly, brazing),as well as material cost (for example, only one pair of manifold, onlyone pair of brackets).

Various types of heat exchangers are found for automotive applications.

A condenser often uses a special type of refrigerant for the cooling.More specifically, a refrigerant such as R-134a, is a widely acceptedindustrial standard. Compared to its predecessor (R-12) or FREON, itsignificantly reduced side effect to the environment. Because of thisimprovement, R-134a has gradually replaced R-12 to become the standardfor air-conditioning refrigerant for auto industry.

Recently, other refrigerants, and, in particular, refrigerants such asgases, are emerging as potential replacements for refrigerants such asR-134a. Among these gases are, for example, CO₂ and HFC32. CO₂ is ahighly potential replacement refrigerants for those such as R-134a,since compared to R-134a, its contribution to the global warming is only1/1300 that of R-134a (on the per unit basis). Therefore, in some partsof world, there will probably be specific need for gas-coolers, such asthose using refrigerants such as CO₂, in the near future. Combo coolerswith gas-coolers, (gas combo-coolers) therefore, appear new in manyapplications.

SUMMARY OF THE INVENTION

Heat exchangers of the present invention will typically include one ormore tubes, one or more end tanks, one or more inlets and outlets, oneor more baffles, one or more fins or a combination thereof. Dependingupon the embodiment of the heat exchanger, various different shapes andconfigurations are contemplated for the components of the heatexchanger. For example, and without limitation, the components may beintegral with each other or they may be separate. The shapes and sizesof the components may be varied as needed or desired for variousembodiments of the heat exchanger. Additional variations will becomeapparent upon reading of the following description.

Heat exchanger assemblies (in automotive applications often referred toa engine cooling assemblies or modular assemblies) comprising a heatexchanger with at least two manifolds and a plurality of tubesconnecting the at least two manifolds, have applicability in automotiveapplications. In particular, heat exchanger assemblies often have aplurality of tubes linking the manifolds in such a way that fluidcommunication is established between at least one of the tubes and theat least two manifolds, and at least one fin, and, preferably, aplurality of fins, is present between the at least one tube in fluidcommunication with the at least two manifolds and at least one othertube.

It has been found that it is also possible to have heat exchangerassemblies comprising a heat exchanger module having tubes, manifoldsand fins, as described above, with other elements that allow functioningof the heat exchanger assembly under conditions heretofore not found inthe automotive environment. For example, use of gas-coolers, such as C0₂coolers, operate at what can be considered high temperature and/or highpressure conditions (high temperature/pressure heat exchanger). Theseconditions are normally not experienced in a traditional automotiveenvironment.

Various aspects of the present invention provide for a heat exchangerassembly for automobile vehicles having a ‘two-rows front to back oftube’ combo-cooler, where tubes of one combo cooler and tubes of anothercombo cooler are all in two rows or ‘two fold’, generally parallel, andseparated by fins. In various aspects, tubes of each cooler portion areconnected to and in fluid communication with manifolds at both tubeends, and same manifolds connect with tubes of each combo-cooler. Atleast at one end of tube, the manifold is two-fold, the manifold havingtwo pieces or being ‘dual’ and generally described as having a frontmanifold and back manifold portion. Each of the manifolds of eachseparate combo cooler is connected by single row tubes. Each leftmanifold and right manifold, has, for example, in various aspects of thepresent invention, a connection between the dual back and front manifoldportions, i.e. the front and back portions are in fluid communication.

Aspects of the present invention comprise an air-conditioning loop usingCO₂ as a refrigerant, but due to CO₂'s nature, several components needto be quite different from those in A/C loop using, for example, R-134a.In systems wherein heat exchanger modules are used, for example, forengine cooling, an assembly also comprising a gas cooler having agas-cooler portion and a non gas heat exchanger (non gas-coolerportion), an aspect of the present invention involves a a gascombo-cooler, for example. A gas-cooler portion of an aspect of thepresent invention, particularly wherein a gas combo-cooler is providedhaving a gas combo-cooler, has a function that a condenser might play ina non gas combo-cooler. The gas-cooler portion rejects heat gatheredfrom inside the vehicle into external air. A strict replacement ofcondenser for gas cooler portion, however, is generally not possible.For example, gases such as CO₂ have specific features. One feature isthe extreme high operating pressure inside a gas-cooler of about 100bars, compared to 16-20 bars inside a condenser.

In various aspects, for example, when a combo cooler condenser portionis replaced by a gas-cooler portion to form a gas combo-cooler,condensation does not exist as in a condenser, inside the CO₂gas-cooler, and the CO₂ temperature inside the gas-cooler is no longer aconstant. The temperature difference between the CO₂ gas and air reducesat faster pace than that for a condenser. In a use such as a gascombo-cooler, as in one aspect of the present invention, both gas-coolerportion and other cooler portion (non gas-cooler, such as oil cooler,for example), need to be more optimized since the general design foundin combo-coolers has generally used the same front area, and a radiatorwhere present, and therefore, each cooler portion of the combo will havea very limited front area, which results in further requirements inthermal efficiency. The present invention overcomes such deficiencies.

Gas-coolers have characteristics and, in the case of two row or‘two-fold’ gas-coolers, designs that are different from a normally onerow (‘one fold’) condenser or one row (‘one fold’) radiator or acombination of two one fold heat exchangers connected with a common pairof manifolds (a non-gas combo-cooler). By gas combo-cooler, it is meanta design wherein a gas cooler, of two fold design, also comprises heatexchanger portions that form part of a non-gas combo cooler, the non gascombo-cooler portions being each of a one fold or two fold design.

The present invention, in various aspects, allows for high temperatureand/or pressure heat exchanger, such as a gas-cooler, to be integratedinto a combo-cooler, using, for example, a two-row (‘two-fold’) tube andcore gas-cooler, to create an assembly comprising two-combo coolers. Byproviding for a higher thermal efficiency design, both gas-cooler andoil cooler, for example, can be found in a heat exchanger assemblycomprising a combo-cooler in a gas combo-cooler. In various aspects ofthe present invention, a range of hydraulic diameter 0.2 mm-2 mm isprovided; thereby enhancing and/or optimizing the tube/fin surfacerelationship in a heat exchanger having a two-fold combo-cooler.

A heat exchanger assembly, in accordance with an aspect of the presentinvention, can be made up of heat exchangers, which in the assembly aretermed as heat exchanger portions, as they are part of the combo coolermodule. A non gas-cooler portion and a gas-cooler portion are requiredas part of each combo-cooler module. As examples, a non gas-coolerportion can include, for example, oil coolers such as transmission oiland power steering oil coolers, radiators, charge air coolers,condensers, fuel coolers, and other such heat exchangers.

In one embodiment of the present invention, each portion of manifold(front/rear) has at least one chamber or ‘space’ formed by baffles whichseparate the manifold into portions depending on the type of fluid thatis designed to flow therethrough. Each space and has at least oneleak-detection hole towards external side.

Aspects of the present invention provide for a two-fold gas-cooler aspart of a heat exchanger assembly that also includes a non gas-coolerheat exchanger, such as an oil cooler or combo-cooler, that is also oftwo-fold tube design.

The present invention, in various aspects, provides for a hightemperature and/or pressure heat exchanger that can operate with themanifolds, tubes and fins of heat exchanger portions such as those foundin combo-coolers that are non gas combo-coolers. A manifold provides foran overall grouping of the heat exchanger components, and, as such, areplaced at the end of the core of the heat exchanger, where fluid thatcirculates in the tubes can access the manifold. The manifold can be asingle manifold (for example, a manifold that encompasses or containstubes from gas-cooler portions from both the front and the back of a gascombo-cooler), or a two piece or dual manifold, wherein each portion ofa gas-cooler, both front and back, is respectively part of a separatepiece or manifold that encompasses or contains only the tubes that areat the front or back of the gas-cooler portion of the gas combo-coolerrespectively. In various aspects of the present invention, hightemperature and/or pressure heat exchangers which avoid inter-coolerinternal leaks or leakage often present in heat exchangers under hightemperature/pressure by having a detection and/or pressure release means(‘detection means’) such as a detection holes, on the manifolds isprovided.

In various embodiments of the present invention, at least one tube of atleast one cooler has sub-passageways, and the product of hydraulicdiameter of the tubes of at least one tube of each of the coolers of thegas combo cooler falls within the following range: 0.15 mm2<Dg Do<8.0mm2.

In various aspects of the present invention, a gas combo-cooler assemblyis described comprising two combo-cooler modules for high pressureapplications. At least one portion of the module comprises a heatexchanger that operates under high temperature and/or high pressureconditions (‘high pressure heat exchanger’). In aspects of the presentinvention, a heat exchanger assembly for automotive vehicles comprisinga gas combo-cooler having two combo cooler modules is described, eachcombo cooler module having: a gas cooler portion; a non gas coolerportion; a first manifold; a second manifold opposite the firstmanifold; a plurality of first tubes in fluid communication with thefirst and second manifolds, the plurality of first tubes adapted to havea first fluid flow therethrough; a plurality of second tubes in fluidcommunication with the first and second manifolds, the plurality ofsecond tubes adapted to have a second fluid, different from the firstfluid, flow therethrough; a plurality of fins disposed between the firstand second tubes, with the first and second tubes and fins beinggenerally co-planar relative to each other.

In various aspects of the present invention, at least one manifold ofeach combo cooler module has a fluid connection means between eachother. In various aspects, a fluid connection means between front andback manifold or manifold parts in a gas combo cooler heat exchanger,wherein a fluid connection means is between the at least one manifold ofthe first combo cooler module and the at least one manifold of thesecond combo cooler module.

The fluid connection means can be channel, orifice, or tube, or anyother connection device whereby fluid can flow from one manifold toanother manifold, or in the cases of multi piece manifolds, from onepiece or part to another piece or part of the multi piece manifold. Forconvenience, each combo cooler portion or module shall be described ashaving manifolds, for example, having one first part wherein one firstfluid flows and a one second part wherein one second fluid flows. Byfront and back manifolds, it means one manifold associated with onecombo cooler module, and another manifold with a second combo coolermodule.

In various aspects of the present invention, heat exchanger is provided,wherein the first and the second manifold are separated into parts, onepart of the manifold in communication with the plurality of first tubesand another part of the manifold in communication with the plurality ofsecond tubes.

Each combo-cooler module comprises a high pressure heat exchanger havingat least two manifolds on opposite sides of a set of essentiallyparallel tubes, the at least first manifold on one side of the set ofessentially parallel tubes and the at least second manifold on the otherside of the set of essentially parallel tubes. In aspects of the presentinvention, at least one first (front) manifold and at least one second(front) manifold is in combination, respectively, with a third manifold(back) manifold and a fourth (back) manifold the first and thirdmanifold forming, for example, a two piece manifold and the second andfourth manifold forming, for example, a two piece manifold.

In aspects of the present invention, the first and third manifold can,alternatively, be in actuality, a one piece manifold that encompassesthe tubes of both back and front sections of the gas combo-cooler, thecore sections of the two non gas combo-coolers preserving theirindividual fluids without mixing of either of each combo cooler coreportion. In other aspects, a communication means may be provided betweenthe one piece or between two pieces of a two piece manifold in the areaof the non gas combo-cooler portion such that a fluid communicationbetween the non gas front and back combo cooler portions can occur.

In various aspects of the present invention, a gas combo-cooler islocated in front of radiator of engine. In other words, the combo-cooleris in the up-stream of air-flow, and the radiator is in the down-streamof the air flow. In other aspects, the heat exchanger assembly with gascombo-cooler, has a non gas cooler that comprises an oil cooler, and, inparticular, a two pass oil cooler portion, where the first pass of oilis in a row of tubes in back of or the down-stream of air-flowdirection, and during the 2^(nd) pass the same tubes are up-stream ofair-flow direction.

In aspects of the present invention, the gas combo-cooler has portionswherein the bottom, middle or top portion, or combinations thereof, havetwo fold or dual tubes associated with one type of cooler portion (forexample, a CO₂ gas-cooler), while the front row tubes and rear-row tubesof another cooler portion, has one fold or one row tubes for eachdifferent coolers (for example, transmission oil cooler for frontcooler, and rear cooler for power-steering oil cooler).

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 shows a non-gas combo-cooler module having oil cooler portionlocated at the top of combo-cooler, and a condenser portion at thebottom of combo-cooler module.

FIG. 2 shows a non-gas combo-cooler module having an oil cooler portionat the top of the combo-cooler, and a condenser portion at the bottom,with all tubes in a single row.

FIG. 3 shows a perspective view of a prior art gas-cooler having alayout with two tube rows, one tube row for a first pass and a secondtube row portion for a second pass in the gas-cooler.

FIG. 4 shows a gas combo-cooler assembly having with a two-fold twopiece manifold, the first manifold in fluid communication with the thirdmanifold, in accordance with an aspect of the present invention.

FIGS. 5, 6 and 7 show schematic diagrams of the basic layout of a gascombo-cooler module comprising high internal pressure cooler portion,like CO₂ gas-cooler.

FIG. 5 a shows a front-view of a gas combo-cooler including gas-cooler,with gas-cooler tubes and tubes of other coolers basically in parallel,with pairs of manifolds linking the tubes, in accordance with an aspectof the present invention.

FIG. 5 b shows a perspective view of two row/fold combo-cooler.

FIG. 6 show a top view of a gas combo-cooler including a gas-cooler,having a two rows of tubes (‘two-fold tubes’) and a two-fold manifold,in accordance with an aspect of the present invention. The two-foldmanifold is physically interconnected, so that fluid communication mayoccur between the manifolds. The two-row tubes of various embodimentslay in the direction of air flow.

FIG. 7 shows a gas combo-cooler module including gas-cooler, having twodetection holes in a front manifold, on the same level as two detectionholes in a rear manifold of the two piece manifolds, in accordance withan aspect of the present invention.

FIG. 8 is a top down schematic view of a one pass oil cooler portion(gas combo cooler portion not visible) of a combo-cooler module, with anoil inlet on one side of manifolds and an oil outlet on the other sideof manifolds, in accordance with an aspect of the present invention.

FIGS. 9 a and 9 b show a top down schematic view of a heat exchangerassembly having gas combo-cooler, the two combo-cooler modules having anoil inlet and oil outlet on the same side of the manifold (s), inaccordance with an aspect of the present invention.

FIG. 10 illustrates an assembly having an engine cooling module, theassembly having two-folds/two piece configurations having two tuberowed, two-fold gas-cooler in front of a radiator, so that the radiatoris downstream the direction of airflow in normal operation of thevehicle, in accordance with an aspect of the present invention.

FIG. 11 shows a schematic side view of a gas combo-cooler where thefront or first manifold and rear or second manifold have detection holesat different levels, in accordance with an aspect of the presentinvention.

DETAILED DESCRIPTION OF VARIOUS EMBODIMENTS OF THE PRESENT INVENTION

FIG. 1 shows a common combo-cooler layout: an oil cooler (10) is locatedat the top of combo-cooler (13), and a condenser (11) is located at thebottom of the combo cooler (16). All tubes (22) are in a single rowbetween manifolds (21), as shown in FIG. 2.

FIG. 3 shows a gas-cooler layout with two tube-rows (36, 37). Air flowsthrough the first tube row (B), and then second tube row (A).

Refrigerant flows through two-fold tubes that communicate with oneanother. Corresponding manifold also has a design wherein a pair ofmanifolds (dual front and rear (back) manifold) replace a singlemanifold, and the front manifold communicates with the rear manifold.

FIG. 4 shows a manifold design for a gas combo-cooler (43) with two-fold(dual) manifolds (41, 42) in fluid communication (44) with one another.

In various aspects of the present invention, a heat exchanger assemblymay be a brazed assembly or made of modules or components.

Integration of the higher internal pressure cooler (for example, agas-cooler of CO₂) into a combo-cooler (not shown) is envisioned, inother aspects of the present invention.

FIGS. 5, 6 and 7 show schematically a layout of combo-cooler, includinga high internal pressure cooler, for example a CO₂ gas-cooler, where CO₂is the fluid which flows in the tube. By fluid, it is meant a gas orliquid that has flow characteristics that allow the substance to flow ineither gaseous or liquid flow, through ‘conducts or ‘tubes’ of a heatexchanger assembly.

FIG. 5 shows a front-view of the gas combo-cooler including gas-coolers.Gas-cooler (500(a)) and another heat exchanger such as a non gas coolerportion (500(b)), share the same pairs of dual manifolds, and divide thefrontal area of the gas-combo-cooler (510) into two or more, especiallytwo or three, two tubes for combo-cooler of two coolers, three tubes inthe case of tri-cooler, tubes (501) of gas-cooler (500(a)) are connectedthe pairs of manifold (503(a), 503(b)) by both tube ends (501(a),501(b)), and tubes of other heat exchangers (506) are also connected tothe same pairs of manifolds (503(a), 503(b)) by both tube ends (506(a),506(b)), fins (502(b)) are in between tubes, at least one fin (509) isbetween one gas-cooler tube (501) and tube of other cooler (506). Onepart (P1) of manifold is in connection with the plurality of firsttubes; one part (P2) of manifold is in communication with the pluralityof second tubes.

In general, tubes of gas-cooler, tubes of other heat exchangers‘coolers’ and fins are essentially in parallel, and the pairs ofmanifolds are essentially perpendicular to the tubes.

FIG. 5 b show a side-view of a heat exchanger assembly with non-gasportion (521) combo-cooler and CO₂ gas-cooler portion (520). Each offour manifolds (front-left, front-right, rear-left, rear-right, has atleast one non-communicating chamber or space (522), separated by abaffle (524) of gas-cooler (520), and a baffle (523) of another non-gasheat exchanger or cooler. By non-communicating chamber or space it ismeant a chamber that has no communication with tubes (gas-cooler tubesor other cooler tubes) with one another. A non-communicating space canalso occur where one or more tubes are connected into a space, howeverthis (these) tube(s), are not in fluid communication with other tubes.In other words, this tube is normally called, in the art, a ‘dead tube’.

The non-communicating chamber (522) has an orifice or hole (525, 526)that extends from the internal surface to the external surface of thenon-communicating chamber (522). This hole towards external side servesas a detection means (526) so that any possible leak from one ofcombo-coolers portions leads to refrigerant not going into anothercooler directly, but passing external to the manifold where its presencecan be detected.

In order to avoid any leak, the two chambers (525) (528) inside the twofront manifolds (500(a)) (500(b)), for example, are at the same level.The two detection holes (525) (526) in the two front manifolds (500(a),500(b)) are located between the same boundary gas-cooler tube and thesame boundary other cooler tube.

The detection holes (525, 526) or holes are located in the space (522,528) between the baffles (523, 524). Communicating means (X, Y) betweenfront (520(a)) and back (520(b)) dual manifold are illustrated.

FIG. 6 shows a top view of a heat exchanger assembly (600) havingcombo-cooler module portions that are non-gas heat exchangers (notshown) and including a gas-cooler portion. Two rows of tubes (602(a),602(b)) form two-fold tubes. The manifold 607(b), 603(b) and 607(a)603(a) are a two-fold or dual manifolds. The two-fold/dual manifolds isphysically connected at area (608(a), and at area (608(b)) where fluidcommunication occurs between the manifold. The two-fold tubes (602(a),602(b)) lay in the direction of air flow A, and tubes are connected to afirst manifold (603(a), 603(b)) and a second manifold (607(a), 607(b))in an essentially parallel configuration.

FIG. 7 pertains to a similar heat exchanger assembly having combo-coolermodule portions that are non-gas heat exchangers and including agas-cooler portion. Two rows of tubes form two-fold tubes. A manifold istwo-fold as well. The two-fold/dual manifold is physically connected atareas and at one area fluid communication occurs between the dualmanifold. The two-fold tubes lay in the direction of air flow, and areconnected to a first manifold and a second manifold in an essentiallyparallel configuration. Because of the extreme high internal pressure ofthe CO₂ gas-cooler (700), a leak detection means (701) is provided toshow potential leaks prior to final shipping to customers.

FIG. 7 b illustrates two sets of tubes having a single manifold (730)with varying separation to prevent fluid flow contact where not desired.

As can be appreciated numerous detection holes, in numerous areas ofmanifold, are possible when chambers or ‘spaces’ between fluid or baffleexist.

In FIG. 7, the at least one detection hole (701(a)) in at least onefront manifold (750(a)) is on the same level as at least one detectionhole (701(b)) in the rear manifold (750(b)).

FIG. 8 illustrates an oil cooler portion of a gas combo cooler of anexternal air conditioning loop and oil cooling loop, the heat exchangerassembly comprising a gas combo-cooler having gas-cooler portion withmanifold(s) (807(b), 803(b) and 807(a) and 803(a)) inlet/outlet means(I, O) such as blocks, pipes or tubes, or the like. The inlet /outletmeans (I, O) can be on the same manifold or on the opposite manifolds.FIG. 8 shows one example of 1-pass oil cooler and a non gas combo-coolerportion of the heat exchanger assembly. Oil inlet (I) is at one side ofthe manifolds (RT) (right manifolds), and oil outlet (O) is at the otherside of manifolds (left manifolds) (LT).

FIGS. 9 a and 9 b illustrate the heat exchanger assembly having use inan external air conditioning loop and oil cooling loop, having a heatexchanger assembly comprising a non-gas combo-cooler portion andgas-cooler portion with manifold(s) and inlet/outlet means such asblocks, pipes or tubes, or the like another aspect wherein oil inlet (I)and outlet (O) are on the same side of the manifold or manifolds(907(a), 903(a) and 907(b), 903(b)) (right side (RT), for example). Inan embodiment with a two pass oil cooler, FIG. 9 a illustrates aconfiguration where oil can flow first through the rear row tubes(902(a)), and then comeback through the front-row tubes (902(b)). FIG. 9b shows a configuration where flow goes in the opposite direction, firstthrough the front-row tubes, than through the rear row tubes.

Thermal efficiency of a gas combo-cooler is achieved by providing a gascombo-cooler with the following attributes: the product of hydraulicdiameter of gas-cooler (Dg) and hydraulic diameter of the non-gas-cooler(Do) between about the following range:0.15 mm²<Dg Do<8.0 mm².

In various aspects, the two-fold (two row) gas combo-cooler (sometimesreferred to as a combined combo-cooler) has a distribution of thermalresistance such as the following. For combined combo of gas-cooler andoil cooler, the gas-cooler, external air side thermal resistancerepresents between about 70%-80% of total thermal resistance, withinside tube thermal resistance between about 20%-30%. For combinedcombo-cooler having a transmission oil cooler and gas-cooler only,however, external air side thermal resistance is between about 35% to45%, and inside tube thermal resistance is between about 55%-65.

In various aspects of the present invention, more surfaces are provideat the external air side of the gas-cooler or gas cooler portion, thewetted areas (wet surface area) of the tubes of the oil cooler portion,on a per tube basis, being larger than the wet surface area of the gascooler portion. The following expression summarizes this relationship(on the per tube basis):Surface_OilnsideTube/Surface_externalAir>Surface_GasInsideTube/Surface_externalAir

In various aspects, fins are used within the non gas combo-coolerportion of the gas combo cooler, in accordance with an aspect of thepresent invention, are the same, or, different from one another. Thefins used with the gas cooler portion of the gas-combo-cooler are alsothe same, or different from those used with the non gas-cooler portion.

Where the same type of fins is used for both cooler portions, the aboveexpression can be simplified as:Surface_OilInsideTube>Surface_GasInsideTube

Another aspect of the present invention provides for a gas combo-coolerin front of a radiator. FIG. 10 illustrates a heat exchanger assembly inan engine cooling module with two-folds configurations having two-rowgas-cooler (Z) in front of a radiator (100). In the air flow direction(A), the combo-cooler (Z) is upstream, and radiator (1000) isdown-stream of the air flow. Radiator manifold (1001) and core (102) areshown. Dual manifold (1101, 1103) is illustrated as well as tube (1101)of one gas combo cooler portion.

Tubes are preferably arranged so that they have at least one fin (notshown) and, preferably, fins that contact at least two of the tubes. Twotubes can have fins that are in one row or in two rows (two-fold fins).Therefore, fins can be internal to each non gas combo- cooler core ofthe each non-gas cooler portion or between cores of each non gas coolerportion of the gas combo cooler.

FIG. 11 shows a schematic side view of a gas combo-cooler (1110) wherethe front manifold (1114) and rear manifold (1113) have their detectionholes (1112, 1111) at different levels. Baffles (1118) are illustratedwhich form manifold spaces or chambers internally (1200).

The number of passes for the gas-cooler portion of the gas combo-cooleris usually small. For example, the number of passes for an oil coolerportion is preferably less than 4, more preferably 1-3 passes and morepreferably, either 1 or 2 passes.

According to one aspect of the invention, the heat exchanger willcomprise a plurality of components that are assembled together bysuitable joining techniques. In one preferred embodiment, one or more ofthe components of the heat exchanger such as the baffles, the end tanks,the tubes, fins, the inlets, the outlets, a bypass or combinationsthereof may be attached to each other using brazing techniques. Althoughvarious brazing techniques may be used, one preferred technique isreferred to as controlled atmosphere brazing. Controlled atmospherebrazing typically employs a brazing alloy for attaching componentswherein the components are formed of materials with higher meltingpoints than the brazing alloy. The brazing alloy is preferablypositioned between components or surfaces of components to be joinedand, subsequently, the brazing alloy is heated and melted (e.g., in anoven or furnace, and preferably under a controlled atmosphere). Uponcooling, the brazing alloy preferably forms a metallurgical bond withthe components for attaching the components to each other. According toone highly preferred embodiment, the brazing alloy may be provided as acladding on one of the components of the heat exchanger. In such asituation, it is contemplated that the components may be formed of amaterial such as a higher melting point aluminum alloy while thecladding may be formed of a lower melting point aluminum alloy.

Envisioned are also gas combo-coolers that are tri-coolers orquad-coolers. For example, in the two-fold row tube gas combo-coolerconstruction, a gas-cooler can be located at the bottom of the heatexchanger assembly (both front row and rear row tubes), a transmissionoil cooler (TOC) at the top front-row of tubes, and a PSOC (powersteering oil cooler) at the top rear (back) row of tubes.

Fins may be used for heat exchange portion of the gas combo-cooler ornon-gas combo-cooler. Though different heat exchange cooler portions mayuse different tubes, but use the same kind of fins. They may also usedifferent types of fins. By different types of fins, it is meant finsthat vary in physical characteristics, such as height, pitch, thickness,materials, for example.

Unless stated otherwise, dimensions and geometries of the variousstructures depicted herein are not intended to be restrictive of theinvention, and other dimensions or geometries are possible. Pluralstructural components can be provided by a single integrated structure.Alternatively, a single integrated structure might be divided intoseparate plural components. In addition, while a feature of the presentinvention may have been described in the context of only one of theillustrated embodiments, such feature may be combined with one or moreother features of other embodiments, for any given application. It willalso be appreciated from the above that the fabrication of the uniquestructures herein and the operation thereof also constitute methods inaccordance with the present invention.

The preferred embodiment of the present invention has been disclosed. Aperson of ordinary skills in the art would realize, however, thatcertain modifications will come within the teachings of this invention.Therefore, the following claims should be studied to determine the truescope and content of the invention.

1. A heat exchanger assembly for automotive vehicles comprising a gascombo-cooler having a first and a second combo cooler module, each combocooler module having: a gas cooler portion; a non gas cooler portion; afirst manifold; a second manifold opposite the first manifold; aplurality of first tubes in fluid communication with the first andsecond manifolds, the plurality of first tubes adapted to have a firstfluid flow therethrough; a plurality of second tubes in fluidcommunication with the first and second manifolds, the plurality ofsecond tubes adapted to have a second fluid, different from the firstfluid, flow therethrough; a plurality of fins disposed between the firstand second tubes, with the first and second tubes and fins beinggenerally co-planar relative to each other.
 2. The heat exchanger, as inclaim 1, wherein a fluid connection means is between the at least onemanifold of the first combo cooler module and the at least one manifoldof the second combo cooler module.
 3. The heat exchanger, as in claim 2,wherein the first and the second manifold are separated into parts, onepart of the manifold in communication with the plurality of first tubesand another part of the manifold in communication with the plurality ofsecond tubes.
 4. The heat exchanger, as in claim 3, wherein the fluidconnection means is between the part of the manifold in fluidcommunication with the plurality of first tubes.
 5. The heat exchanger,as in claim 3, wherein the fluid connection means is between the partsof the manifold in fluid communication with the plurality of secondtubes.
 6. The heat exchanger assembly, as in claim 5, wherein the partof the manifold in fluid communication with the plurality of secondtubes is the non gas cooler portion, and the non gas cooler portion is atwo fold cooler.
 7. The heat exchanger assembly as in claim 5, whereinthe part of the manifold in fluid communication with the plurality ofsecond tubes is the non gas cooler portion, and the non gas coolerportion is a one fold cooler.
 8. The heat exchanger assembly, as inclaim 4, wherein the part of the manifold in communication with theplurality of first tubes is the gas-cooler portion, and the part of themanifold in communication with the plurality of second tubes is the nongas cooler portion.
 9. The heat exchanger assembly as in claim 8,wherein the gas fluid portion of the gas combo-cooler has fewer than 4passes.
 10. The heat exchanger assembly, as in claim 9, wherein thetubes have an external air side relative to the direction of air flowand the external air side thermal resistance of the gas cooler portionis between about 35 and 80% of the total thermal resistance.
 11. Theheat exchanger assembly, as in claim 9, wherein the inside tube thermalresistance is between about 20 and 65% of the total thermal resistance.12. The heat exchanger assembly, as in claim 10, wherein the internalsurface of the tubes is the wetted side of the tubes, and wherein thesize of the wet surface area of the tubes of the gas cooler portion issmaller than the size of the wet surface area of the non gas coolerportion on a per tube basis.
 13. The heat exchanger assembly, as inclaim 12, wherein theSurface_oilnsideTube/Surface_externalAir>Surface_GasInsideTube/Surface_externalAir.14. The heat exchanger assembly, as in claim 6, wherein the non gascooler portion has at least two types of tubes.
 15. The heat exchangerassembly, as in claim 6, wherein the hydraulic diameter of the tubes ofthe gas cooler is Dg and the hydraulic diameter of the non-gas cooler isDo, and the product of hydraulic (Dg) and (Do) is given by the followingequation:0.15 mm²<Dg Do<8.0 mm².
 16. The heat exchanger assembly, as in claim 14,wherein the non gas cooler portion is part of a non gas combo cooler.17. The heat exchanger assembly, as in claim 14, wherein the non gascooler portion is part of a non gas combo cooler.
 18. The heat exchangerassembly, as in claim 18, further comprising at least onenon-communication chamber in at least one manifold and at least onedetection means.
 19. The heat exchanger assembly, as in claim 18,wherein at each non-communication chamber has at least one detectionmeans.
 20. The heat exchanger assembly, as in claim 18, wherein at leastone detection means is located on at least one manifold of the first andthe second combo cooler manifold, and wherein the detection means are atapproximately the same level.
 21. The heat exchanger assembly, as inclaim 18, wherein at least one detection means is located on at leastone manifold of the first and the second combo cooler manifold, andwherein the detection means are at different levels.